Method of forming hollow articles



Feb. 5, 1929.

F. P. VINCENT METHOD FORMING HOLLOW ARTICLES Filed Aug. l8.- 1922 2 Sheets-Sheet 1 BYW W FRANK RVINCENT INVENTORY HIS? ATTORNEY-'5 F. P. VINCENT METHOD OF FIORMING'HOLLOW ARTICLES Feb 5 1929.

Filed Aug. 18. 1922 2 Sheets-Sheet 2 INVENTOR Hm A WT v TTQRNEYS.

Patented Feb. 5, 1929. e v

UNITED STATES v 1.700.7 PATENT o-FF c-s.

rm]: 2. vmcnn'nor mm, 0310, assrenon, BY MES-NE ASSIGNMENTS, To, s'rnnr.

m 'rnnns, mc., or CLEVELAND, onro, A coRronA'rIoNor orno. n

Israel: or FORMING HOLLOW ARTICLES.

Application am August 18, 19 2. Serial No. 582,588. I

. An object of my present invention. is to provide a process whereby such tubes after being rolled may be brazed, and then when so brazed so as to make a substantially oval tube, to subject the tube to pressure in agpress in such a way that undesirable inequalities in the form of the brazed tube will be eliminated, and the tube will be given, if desired,

an irregular oval form, the tube being, as has been before stated, preferably of high carbon steel. 4 Another object of my invention is to provide an improved process for producing a tube so formed that it will have the maximum of rigidity'at an intermediate portion so that they will be highly efficient for the purpose of forming portions of structures such as bed spring side frame members and the like.

Another object. of my invention is to provide a process for forming the tube having a general oval cross sectional shape with ends which are substantially circular,lwhen this p is desired, for the purpose of fitting attaching brackets having circular openings to the ends 'of the tubes, such, as for instance, bed

spring side frame member end brackets. My invention will be better understood by reference to the accompanying drawing which shows apparatus for carrying out the process of my invention. Referring to the drawingsi Fig. 1 shows a front elevational view of a machine adapted to carry out my invention. view of the Fig. 2 shows. a side elevational machine illustrated in Fig. 1.

Fig. 3 shows a plan view of a tube formed in accordance'with my invention.

Fig.4 is asimilar view of the same tube as shown in Fig. 3 except that the View is taken from a point at right angles to that of Fig. 3.

Figure 5 is an end elevatidn f the tube of Figures-'3 and "4.

- nally extending grooves 6 for the. lower die,

Fig. 6 shows'aplan view of a nio'di fied form of the tube formed in=accordance with another embodiment o fmy invention.

Fig. 7 shows a plan view of the tube of Fig. 6 takenfrom the point at right angles, to that ofFig.6. 1 'Figure 8 is an end elevation of the tube of Figures 6 and 7. i

Fig. 9 shows a perspective view of the die plates employed to compress the tube ends of the oval tubes of Figs. 6 and-7 into substantially circular cross sectional shape.

Figures 10, 11, 12, and -13 are transverse 7 sections of the tubes of Figures 4 to 8, taken, respectively, on lines -10. 10, llI-ll, 1212, and 13-13 of Figures 4 and 6.

Referring now to the drawings in: all of which like reference characters indicate like parts, at 1, I show the frame of a ,press'adaptable for use in carrying out my invention. At 2, I show a lower'jaw for the said press rigidly mountedtherein, and at 3, I show a reclprocating upper jaw for the press, at 4 I show a forming die mounted on the upper surface of the lower aw 2, and at 5 I show an upper forming die member, secured to the upper or reciprocating press jaw on its under side, the two forming dies presenting their forming faces toward each other, and'in the forming faces of each I provide longit-udi and 7' for the upper die, these grooves are preferably of. uniform cross-section throughout the length of the die, the surface of each groove being a cylindrical surface of less than 180 extent. Y

The grooves 6 and 7 when the dies 4 and 5 are brought nearly, but preferably not quite, together by downward movement of the up, per reciprocating jaw carr ing the upper, die, defines an approximately-oval openin extending the full length of thedies, the opening, however, being preferably normally symmetrical with regard to lateral cross sectlons throughout its length, the opening comprising opposing portions each constituting 100 something less than a half circle, such lportions being brought nearlytogether. The 1 opening under such conditions will also correspond closely to the outside dimensions of the brazedtubes to broperated upon, 105 although there will be a slight difl'erence in that the vertical dimension of the opening under such a condition would be slightly less than such outside dimensions. I

The material for thetubes is rolled into sheets of high carbon steel of the requisite thickness and width, being rolled into tubular form, the rolling giving the tubes a form substantially cylindrical, the diameter of the cylindrical tubes thus prepared being such that the tube when flattened to make it take the desired oval shape as described in connection with thelatter steps of the process employed, will produce a tube having the requisite major and minor cross-sectional axes dimensions. we

The seams of the tubes thus prepared are now brazed, or the edges at the seam secured together in any other suitable way, but I prefer to braze'such a seam, it not being neces ary for the purpose for which I use such tubes, to make a fluid tight scam, it only being essential for the purposes for which my tubes are intended to secure a strong joint not a tight jointnec'essarily, although my invention might be employed in connection with such structures where a tight joint might be desirable. The tubes-may be cut to length either-before or after brazing, but I prefer to .cut them to length before the brazing.

The brazed tubes, substantially of cylindrical shape and of proper length, are now introduced into the press having the die plates 4 and 5 as before described, the cylindrical tube being placed in the groove 6 for the lower die plate.

Now, prior to the operation of the press,

and before the press is used to form these tubes of proper irregular oval shape, and preferably when the lower die plate 4 is'being positioned on the jaw 2, I place preferably between the die plate 4 and the lower jaw 2, near the ends of the jaw such as at 10 and 11,

sheets of paper or like equivalent material for the purpose, of proper thickness such as paper having a thickness of .0O8 inches, so

, cause power.

that the lower die plate is supported at either end on the paper sheets and secured to the lower jaw 2 with the paper sheets near the ends of the jaw, and between the die and the aw. V J The cylindrical tube now being positioned as before described in the groove in the lowermost die plate, the operator by operating the press as by ste ping on the pedal lever 8' will rom the motor 9 operating through suitable gears to cause the jaw 3 to descend vertically to such a distance that the A tube will be pressed between the upper, and

lower. die grooves to such an extent that the pressure will cause the lower die plate 4 and to a lesser extent, the upper die pla e 5, to yield slightly at their intermediate ortions so thatthe pressure on the intermediate portion of thetube will be relieved relative to the pressures at the ends of the-tube, and the diflz'erence in pressures will be gradual,

lessening from the ends of the tube towards the center of the tube. a I find that a tube so formed is wider in the direction of itsminor axis at the middle portion than it is at the ends, though not so wide in the direction of itsmajor axis, and that,

cally negligible loss due to fculls which under previously known processes-for making oval tubes from steel of this character, has been very serious, which loss is now practically eliminated.

Such tubes, as shown in Figs. 3 and 4, may be used as bed spring side frame members, since due to their form whereby the thickness is greater at their intermediate portions, they resist bending, and especially twisting stresses such as are incidental to the use of such si'de frame members in practice; these side framemembers may be suitably attached to the end frame members of a bed spring, such end frame members being of angle iron or other forms, in'any desired way, as by forming flanges on the ends of the tubes, or by brackets having tube end receiving sockets andattaching flanges.

In Figs. 6 to 8 inclusive, I illustrate a different form of irregular oval tube which may be produced by my invention. In this embodiment of my invention, after the tube has passed through the processes as before described, the ends ofthe tubes areinserted be tween die plates 12 and 13, Fig. 9, for a short distance, and the die plates are then brought together to compress the tube, thetube being so inserted that its major axis is in substantially a vertical plane, the co-operating grooves 14 and 15 which compress the ends ofthe tubes 16 and 17, Figs. 6, 7 and 8,.- are p of substantially semi-circular cross sectional bed spring side frame members.

Having thus described my invention as it may be practiced in varying ways, I wish it to be understood that other forms of tubes than those specifically illustrated are contemplated in my invention, and that my invention is not limited to the precise means and methods herein illustrated and described, but the spirit of my invention may be had in structures departing widely therefrom.

I claim-- 1. The method of forming a hollow article having a varying cross sectional configuration which comprises simultaneously applying to an article of uniform cross section distorting pressures of varying amounts.

2. The method of forming a hollow metal article having varying cross sectional configurations which comprises applying to an article having a uniform cross sectional configuration, simultaneously and transversely at different parts of the article distorting pressures of varying amounts.

3. The method offorming a hollow metal article having varying cross sectional configurations which comprises simultaneously and transversely applying to an article of uniform cross sectional configuration distorting pressures of varying amounts throughout substantially the entire length of the article.

at. The method of forming a hollow metal article having varying cross sectional configurations which comprises simultaneously and transversely applying to an article of uniform cross sectional configuration distorting pressures of progressively varying amounts.

5. The method 'of forming a hollow metal article having varying cross sectional configurations which comprises applying simultaneously and transversely to an article of uniform cross sectional configuration distorting pressures of amounts varying progressively from the ends to an intermediate point of the article.

6. The method of forming a hollow metal article having varying cross sectional configurations which comprises placing an article having uniform cross sectional configu-' other portions. 7

7. The method of forming a hollow metal article having varying cross sectional configurations which comprises placing an article having a uniform cross sectional configuration between relatively movable dies, advancing the dies towards each other under sufliciont force to deform the tube, permitting portions of one (lie to yield away fromthe other upon the application of said. force, the extent of such yielding being sufl'icient to vary the cross sectionalconfiguration of the finished article as desired, and varying progressively from apoint of minimum to a .point of maximum yielding.

8. The method of forming a hollow article having a varying cross sectional configuration, which comprises simultaneously applying to the article distorting pressures of varying amounts. 9. The method of forming a hollow metal article having varying cross sectional configurations, which comprises applying to the article simultaneously and transversely thereof. distorting pressures of varying amounts throughout substantially the entire length of the article.

10. The method of forming a hollow metal article having varying cross-sectional configurations, which comprises applying to the article simultaneousl distorting pressures of progressively varymg amounts.

11. The method of forming a hollow metal article having varying cross-sectional configurations, which comprises applying simultaneously and transversely to the article distorting pressures of amounts varying progressivelyfrom the ends to an intermediate point of the article.

In witness whereof, I have hereunto signed my name this 15th day of August, 1922.

FRANK P VINCENT. 

